If you take any vitamins, chances are you’re aware of the benefits of a good multivitamin / mineral and fish oil. You may even consider them the cornerstones of the various supplements you take.

Well, recently, I recommended to someone get on a good multivitamin / mineral and fish oil for their deteriorating health. Then for the next five minutes I got an earful as he explained he did not trust the supplement industry and questioned what was really in those bottles.

And I agreed. Take for instance a couple of recent case studies that were published in the Journal of endocrinology and metabolism in December 2011.

In December 2009, a 57 year old man went to his doctor with the complaints of fatigue, being very thirsty, urinating a lot, and difficulty with his memory. This had been going on for three weeks. His blood work showed very high calcium levels. Since everything else was normal, the doctor suspected high levels of vitamin D (which can elevate calcium in the blood).

As you might have guessed at this point, analysis of one of this man’s nutritional supplements revealed that instead of containing vitamin D in the amount on the label per dosage was (1600 IU), it actually contained 186, 400 IU! To make matters worse, there was an error in the label itself, recommending taking 10 capsules per day instead of one.

If you do the math, that is 1,864,000 IU per day instead of 1600 IU!

And this individual took if for 2 months.

Case two:

A 40 year old man went to his doctor with the complaints of nausea, vomiting, excessive thirst, frequent urination, and aching muscles. Again the blood calcium levels were high.

When his supplements were analyzed, one of them, bought on the internet, stated it contained 1000 IU of vitamin D per daily dose. In fact, the amount per dosage was 970,000 IU.

You may not be aware of this, but the toxic level for vitamin D is estimated to be greater than 100,000 IU per day for at least one month. This means that the first man was taking 18 x the toxic dosage per day and the second man 9x the toxic dosage.

The moral of this story is that it isn’t always enough to read a label.

You really have to do your homework and pick a company that has a good track record of quality control. Companies differ widely in the quality of ingredients used and the frequency and stringency of their testing of these ingredients.